An Interesting Overview of the Meaning and Origins of the term "Sea Change..."

sea change noun [C] LITERARY
a complete change:
There will have to be a sea change in people's attitudes if public transport is ever to replace the private car.

(from Cambridge Advanced Learner's Dictionary)

The phrase is a quotation from Shakespeare. It comes from Ariel’s wonderfully evocative song in The Tempest:

Full fathom five thy father lies:
Of his bones are coral made:
Those are pearls that were his eyes:
Nothing of him that doth fade
But doth suffer a sea-change
Into something rich and strange.

The Oxford English Dictionary finds the first allusive use in one of Ezra Pound’s poems from 1917. But examples can be found a little earlier than that, as in The Great White Wall by Julian Hawthorne, dated 1877: “Three centuries ago, according to my porter, a sea-change happened here which really deserves to be called strange”.
(quoted from the World Wide Words)

Supporting terms and quotations regarding "sea change":

Abar: (Hebrew) To travel in a direction that will change your destiny.

"We cannot become what we need to be by remaining what we are."
(Max Dupree)

"There comes the baffling call of God in our lives also. The call of God can never be stated explicitly; it is implicit. The call of God is like the call of the sea, no one hears it but the one who has the nature of the sea in him. It cannot be stated definitely what the call of God is to, because his call is to be in comradeship with himself for his own purposes, and the test is to believe that God knows what he is after."
(Oswald Chambers, My Utmost for His Highest)

"I have studied many times
The marble which was chiseled for me--
A boat with a furled sail at rest in a harbor.
In truth it pictures not my destination
But my life.
For love was offered me, and I shrank from its disillusionment;
Sorrow knocked at my door, but I was afraid
Ambition called to me, but I dreaded the chances.
Yet all the while I hungered for meaning in my life
And now I know that we must lift the sail
And catch the winds of destiny
Wherever they drive the boat.
To put meaning in one's life may end in madness,
But life without meaning is the torture
Of restlessness and vague desire--
It is a boat longing for the sea and yet afraid.
(Edgar Lee Masters)

" Don't ask yourself what the world needs. Ask yourself what makes you come alive, and go do that, because what the world needs is people who have come alive."
(Gil Bailie as quoted in Wild At Heart by John Eldridge)

"Give me a spirit that on this life's rough sea
Loves to have his sails fill'd with a lusty wind
Even till his sail-yards tremble, his masts crack,
And his rapt ship runs on her side so low
That she drinks water, and her keel ploughs air.

"The place where God calls you is the place where your deep gladness and the world's deep hunger meet."
(Frederick Buechner)